Abstract: Multichannel electrophoresis apparatus employing electrophoretic light scattering as a means for characterizing the particles under study. The apparatus is characterized by the ability to measure light scattered simultaneously using a plurality of local oscillators incident at different angles from the same population of particles being subjected to electrophoresis. The apparatus is used with data processing means to analyze the large amount of scattering data which provide information on electrophoretic mobility, particle size, particle charge, electrophoretic mobility, zeta potential. An important aspect of the new apparatus is a markedly improved capability to segregate data related to diffusion effects from data relating to heterogeneous effects.

Abstract: A headlamp testing method of the invention involves the steps of applying the low beam of the headlamp onto a screen, determining the position of the geometrical center of a closed area of illuminance higher than a predetermined level, determining the position of a cut off line cross point from the position of the geometrical center and a predetermined amount of offset, and determining a presumption line cut off line from the cut off line cross point. The presumption line thus determined is displayed together with a mark which indicates the within which the cross point should fall, and the headlamp beam is judged as being acceptable when the cross point is located within this range.

Abstract: The optical measuring instrument emits a coherent beam of radiation normally to a surface of an object. The scattered radiation generated by the beam of radiation is guided through an optical device to a stationary strip-shaped linear radiation sensor element. The linear radiation sensor element is arranged within a hollow cylinder which is rotatable in an operative position thereof. The hollow cylinder contains a multiple number of slots which traverse the strip-shaped linear radiation sensor element at an acute angle. An evaluation circuit arrangement is connected to the linear radiation sensor element and only generates evaluatable measuring signals during the traversal of one of the slots over a location at the linear radiation sensor element where there occurs a radiation intensity exceeding a predetermined threshold value. Using such measuring instrument it is possible to measure distances with high resolution.

Abstract: An improved method of measuring film thickness of the film layer on a certain material is disclosed. The method is carried out by way of the steps of measuring reflection intensity spectrum, determining extreme values of wavelength relative to the spectrum, preparing an expected value table relative to the reflection interference orders associated with the extreme values of wavelength, calculating a group of expected values of film thickness with reference to the expected value table, calculating deviated values among the values of film thickness in association with the group of expected values, determining the expected orders which minimize absolute values corresponding to deviated values as true interference orders and determining a required film thickness with reference to the thus determined interference orders.

Abstract: In an apparatus for measuring the optical characteristics of an optical system to be examined a light source determines a reference optical axis and generates a light beam that is passed through the optical system to be examined along the reference optical axis. A mask partly transmits the light beam therethrough and has a pattern comprising at least one straight line disposed off the reference optical axis in the light beam, the straight line of the pattern extending in a predetermined direction in a plane substantially orthogonal to the reference optical axis. A photosensitive detector receives the light beam passed through the optical system to be examined and the mask. The detector is fixedly disposed relative to the mask and has a substantial length in a direction substantially orthogonal to the reference optical axis and the straight line of the pattern.

Abstract: The present invention relates to a method and apparatus for measuring the content of suspended substances in a flowing medium by illuminating the medium with light from a light source. Reflected light from the medium is detected by at least two detectors, at least one of which measures directly reflected light while the other detectors measure multiply reflected light. The detector for detecting directly reflected light is located such that a linear relationship is established between its output signal and the concentration of the flowing medium. The other detectors are located such that their output signals will be essentially constant in relation to the concentration of particles in the flowing medium within a large range. The measuring scheme provides for obtaining the quotient of the signal provided by direct reflection divided by the signal provided by multiple reflection.

Abstract: A refractometer comprises a light source, an angle prism and an optical system in a casing so mounted that the optical system focuses an image of a diaphragm at said light source upon a double photodiode located beyond the prism and supported by an oblique surface of the casing. The ratio of the output of one photodiode to the output of the double photodiode is measured to register the index of refraction.

Abstract: In aberration measurement, a light beam from a light source provided at the image plane position of a lens to be examined is caused to enter the lens to be examined, the light beam passed through the lens to be examined, is separated into a plurality of light rays in a plane perpendicular to a principal ray or in a plane perpendicular to the optical axis of the lens to be examined, and the position of each light beam is detected at a position which is spaced apart from a position optically conjugate with said image plane position with respect to the lens to be examined and at which the plurality of light rays can be separated from one another.

Abstract: A method for the stereophotogrammetric survey of a large-dimension object is provided in which the object and a chain having two reference markers thereon spaced apart at a known distance are photographed from a height of about 30 m with two synchronized metric photographic cameras spaced apart by about 6 m. Depth measurements (Z axis) are made on a stereoscopic model reproduced by a stereoplotter at eight sets of points grouped in the eight conventional perimetral locations of photogrammetric orientation at the crests and troughs of the ripples or undulations of the water or ground, respectively. The mean of the depth measurements is calculated to determine the mean horizontal plane and the model is correctly orientated with respect to the horizontal plane by suitable rotation.

Abstract: A lens meter having a focusing indication system with divided-image registration focusing comprises a condenser lens, a target having a nondiffusing transmissive surface and a slit pattern thereon, an objective lens, a lens mount for supporting a lens to be examined, a projection lens, a screen, the arrangement being such that the distance of movement in unison of the condenser lens and the target in the direction of an optical axis is read to detect the degree of the lens supported on the lens mount, an aperture plate disposed in the vicinity of a front focal point of the condenser lens and movable with the condenser lens and the target in the direction of the optical axis, and at least two deflection prisms disposed in intimate contact with the slit pattern on the target and having bases extending across the slit pattern and substantially perpendicularly to each other.

Abstract: A scanning unit comprises offset scanning gratings and light receivers disposed behind respective gratings. The scanning unit is moved past an incremental scale and the receivers are illuminated through the scale and the gratings. Carrier frequency signals which are displaced in phase and are amplitude-modulated in dependence on the pitch of the scale are generated in response to the scanning movement. The phase displacement of the modulation of the carrier signal is evaluated to determine the instantaneously scanned fraction of a scale increment in that a proportional number of clock pulses are counted by a counter. The use of a simple and reliable circuit arrangement and a reliable evaluation are permitted in that the illumination is modulated at the carrier frequency so that the light receivers constitute means for effecting an amplitude modulation of the carrier frequency signal. The amplitude-modulated signal is then processed further.

Abstract: An optical transmitter receiver switch incorporating a fiber optic light guide for communicating between electrically isolated circuits. Each switch has a photoemitter and a photosensor in optical communication with each other and with one end of the light guide. The photosensor and photoemitter are enclosed in an opaque housing and communicate with each other and the light guide via a transparent optical cavity. There results an unusually versatile optical isolator which, when in optical communication with a second optical transmitter receiver switch, forms the preferred relay.

Abstract: A test device for setting motor-vehicle headlight beams is described, which essentially consists of a base plate (1) and the two open-up parts, namely the lens holder (2) and the test surface (3). The lens holder contains an aspheric lens (4) of which the optical axis (5) is parallel to the rest surface (6) of the base plate (1) and simultaneously perpendicular to the test surface when the device is in the opened-up, operational position. The lens is of such height and so corrected that the light of headlights mounted low, normally or high is passed without headlight elevation adjustment and is imaged on the test surface located approximately in the lens focus, and in that the test result is entirely independent of the particular headlight elevation.

Abstract: An invention is disclosed for optically determining the position of an object in space, using a single lens for triangulation, wherein an indexing light beam is projected to a lens on one side nonparallel to the optical axis of the lens. The lens focuses the indexing light beam at a known point on the other side of the lens at or near which reflection occurs by the object. Reflected light is captured by the lens and focused toward a photodetector which generates a signal indicating whether reflection occurred at the known point, thus indicating whether the object is present at the known point. If laser light is used, provision is made for, in effect, positioning the laser light source on the optical axis to reduce the effects of laser pointing instabilities. The invention can be used to measure the radii of rotating gas turbine engine rotors.

Abstract: A non-intrusive method and apparatus for performing qualitative analysis of a liquid disposed within a container transparent to laser radiation comprises a first laser focused at a selected point within the liquid to produce or generate bubbles emanating from that location and a laser Doppler velocimeter which is intercepted by the rising bubbles to produce an output signal indicating both bubble size and velocity, as indication of liquid quality.

Abstract: A method of monitoring the deflocculation of particles in a suspension, which particles, when deflocculated, are such that they can become aligned in an applied field, by applying a beam of radiation to a region of the suspension, applying a field to the region and detecting a change, if any, in forward radiation scattering properties of the region due to the aligning of deflocculated particles, if any, of the suspension in the field.

Abstract: A three dimensional imaging system operating in accordance with the known active triangulation method employs a laser beam that is projected onto an area of a surface the profile of which is to be examined. A beam reflected from such area is received in a position sensitive detector. With synchronised scanning of the projected and detected beams by a system of mirrors, the detected position in the detector remains unchanged when the surface under examination is a flat reference plane, changing only as a measure of the degree of deviation of each examined area from such reference plane in a direction Z. The system is characterised by this basic scanning being carried out in such a way that the beams are scanned in a direction X lying in the beam plane, i.e. the plane defined by the beams, and by a further simultaneous and synchronous scanning that takes place in a direction Y. The directions X, Y and Z are all mutually perpendicular.

Abstract: At least one fiber optic light conductor extends from a source and detection area to a measurement area. In the measurement area, the fiber end is prepared with an end surface slanted relative to the fiber axis and the slanted surface is coated with a reflective material so that light conducted through the fiber is reflected from the end surface and through the side wall of the fiber onto an object being measured. Light is reflected from the object in an amount depending upon the position of the object and reflected light is carried through a similar path by the same or a similar optical fiber to the detector, such that the detector signal correlates to the position of the object.

Abstract: A high-precision alignment pattern for fine-line device fabrication comprises unique marks. The pattern is utilized to align a mask or reticle with respect to a wafer and/or to evaluate actual level-to-level registration achieved between a set of masks or reticles and a wafer. One mark of the pattern comprises two spaced-apart parallel lines. The other mark comprises a notch or arrow-head including an apex portion. In practice, the orientation between the apex portion and the associated parallel lines of the pattern can be read relatively easily with high accuracy.

Abstract: An apparatus for indicating misalignment of the optical elements of an optical system (10) comprises a source (11 ) of optical radiation (which is in general nonpolarized), a beam splitter (12), an optical flat (13) and an off-axis beam sampling device (14). The beam splitter (12) divides an input beam (20) from the source (11) into a transmitted component (21) which passes along the optic axis of the optical system (10) to the optical flat (13), and a reflected component (22) which passes to the off-axis beam sampling device (14). The beam sampling device (14) divides the reflected component (22) of the input beam (20) into two angularly separated beams (24) and (25), which are returned to the beam splitter (12). The beam splitter (12) transmits components (24') and (25'), respectively, of the angularly separated beams (24) and (25) to a detector plane (23).